GitHub Advisoryadvisory · crates.io

GHSA-pph8-gcv7-4qj5 PyO3 Risk of buffer overflow in `PyString::from_object`

LOW Published 2025-04-02 Modified 2025-04-02 Official page ↗
Ecosystem
crates.io
Packages
pyo3
Severity
Low
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
Weaknesses
CWE-125
Reviewed
2025-04-02

Affected packages

• crates.io pyo3: >= 0.1.0, < 0.24.1 → fixed in 0.24.1

Description

`PyString::from_object` took `&str` arguments and forwarded them directly to the Python C API without checking for terminating nul bytes. This could lead the Python interpreter to read beyond the end of the `&str` data and potentially leak contents of the out-of-bounds read (by raising a Python exception containing a copy of the data including the overflow). In PyO3 0.24.1 this function will now allocate a `CString` to guarantee a terminating nul bytes. PyO3 0.25 will likely offer an alternative API which takes `&CStr` arguments.

Related

Weakness · CWE (1)

  • CWE-125 Out-of-bounds Read weakness

References